Can you please open a Terminal window (e.g. KDE's "Konsole" app) and do the following:

1. Run `appstreamcli search chrome` and paste the text that it produces into a comment here

2. Run `plasma-discover appstream://google-chrome.desktop` and see if that works

Also, what version of KDE Plasma are you using?

Thanks!

Hi Nate Graham,
here is what you requested ..... I hope.....
There are three parts to this comment.
Thanks for your help.
Best Regards
Cms

1 of 3: The Plasma version: plasmashell 5.27.10


2 of 3: `appstreamcli search chrome` shows the following

Identifier: com.google.ChromeDev [desktop-application]
Name: Google Chrome (unstable)
Summary: The web browser from Google
Bundle: flatpak:app/com.google.ChromeDev/x86_64/stable
Homepage: https://chrome.google.com/
Icon: com.google.ChromeDev.png
---
Identifier: com.google.Chrome [desktop-application]
Name: Google Chrome
Summary: The web browser from Google
Bundle: flatpak:app/com.google.Chrome/x86_64/stable
Homepage: https://chrome.google.com/
Icon: com.google.Chrome.png
---
Identifier: google-chrome.desktop [desktop-application]
Name: Google Chrome
Summary: 連線到網際網路
Icon: google-chrome
---
Identifier: org.gtk.Gtk3theme.CrosAdapta [runtime]
Name: CrosAdapta
Summary: Chrome OS GTK theme
Bundle: flatpak:runtime/org.gtk.Gtk3theme.CrosAdapta/x86_64/3.22
Homepage: https://chromium.googlesource.com/chromiumos/third_party/cros-adapta/
---
Identifier: com.cocoatech.deckr [desktop-application]
Name: Deckr
Summary: Desktop app used with the Deckr chrome plugin
Bundle: flatpak:app/com.cocoatech.deckr/x86_64/stable
Homepage: https://deckr.surf
Icon: com.cocoatech.deckr.png
---
Identifier: org.bleachbit.BleachBit [desktop-application]
Name: BleachBit
Summary: Cleans files to free disk space and to maintain privacy
Bundle: flatpak:app/org.bleachbit.BleachBit/x86_64/stable
Homepage: https://www.bleachbit.org/
Icon: org.bleachbit.BleachBit.png
---
Identifier: com.github.gabutakut.gabutdm [desktop-application]
Name: Gabut Download Manager
Summary: Simple and Fast Download Manager
Bundle: flatpak:app/com.github.gabutakut.gabutdm/x86_64/stable
Homepage: https://github.com/gabutakut
Icon: com.github.gabutakut.gabutdm.png
---
Identifier: org.chromium.Chromium [desktop-application]
Name: Chromium Web Browser
Summary: The web browser from Chromium project
Bundle: flatpak:app/org.chromium.Chromium/x86_64/stable
Homepage: https://www.chromium.org/Home
Icon: org.chromium.Chromium.png
---
Identifier: com.vivaldi.Vivaldi [desktop-application]
Name: Vivaldi
Summary: A powerful, personal, and private web browser
Bundle: flatpak:app/com.vivaldi.Vivaldi/x86_64/stable
Homepage: https://vivaldi.com/
Icon: com.vivaldi.Vivaldi.png
---
Identifier: camp.nook.nookdesktop [desktop-application]
Name: Nook Desktop
Summary: Nook is an application that plays Animal Crossing hourly themes on the hour.
Bundle: flatpak:app/camp.nook.nookdesktop/x86_64/stable
Homepage: https://nook.camp
Icon: camp.nook.nookdesktop.png
---
Identifier: org.gnome.Shell.Extensions.GSConnect [desktop-application]
Name: GSConnect
Summary: KDE Connect implementation for GNOME
Package: gnome-shell-extension-gsconnect
Homepage: https://github.com/GSConnect/gnome-shell-extension-gsconnect/
Icon: gnome-shell-extension-gsconnect_org.gnome.Shell.Extensions.GSConnect.png
---
Identifier: org.firestormviewer.FirestormViewer [desktop-application]
Name: Firestorm Viewer
Summary: Client for accessing 3D virtual worlds
Bundle: flatpak:app/org.firestormviewer.FirestormViewer/x86_64/stable
Homepage: https://www.firestormviewer.org/
Icon: org.firestormviewer.FirestormViewer.png
---
Identifier: nomacs.desktop [desktop-application]
Name: nomacs
Summary: nomacs is a free, open source image viewer.
Package: nomacs
Homepage: http://nomacs.org
Icon: nomacs_nomacs.png
---
Identifier: com.googleplaymusicdesktopplayer.GPMDP.desktop [desktop-application]
Name: Google Play Music Desktop Player
Summary: Run Google Play Music as a standalone desktop app
Bundle: flatpak:app/com.googleplaymusicdesktopplayer.GPMDP/x86_64/stable
Homepage: https://www.googleplaymusicdesktopplayer.com/
Icon: com.googleplaymusicdesktopplayer.GPMDP.png
---
Identifier: mkchromecast.desktop [desktop-application]
Name: mkchromecast
Summary: Cast your Linux audio or video files to your Google cast or Sonos devices
Package: mkchromecast
Icon: mkchromecast_mkchromecast.png
---
Identifier: org.photoqt.PhotoQt [desktop-application]
Name: PhotoQt Image Viewer
Summary: View and manage images
Bundle: flatpak:app/org.photoqt.PhotoQt/x86_64/stable
Homepage: https://photoqt.org
Icon: org.photoqt.PhotoQt.png
---
Identifier: com.github.Eloston.UngoogledChromium [desktop-application]
Name: ungoogled-chromium
Summary: A lightweight approach to removing Google web service dependency
Bundle: flatpak:app/com.github.Eloston.UngoogledChromium/x86_64/stable
Homepage: https://github.com/ungoogled-software/ungoogled-chromium
Icon: com.github.Eloston.UngoogledChromium.png
---
Identifier: net.cozic.joplin_desktop [desktop-application]
Name: Joplin
Summary: open source note taking and to-do application
Bundle: flatpak:app/net.cozic.joplin_desktop/x86_64/stable
Homepage: https://joplinapp.org/
Icon: net.cozic.joplin_desktop.png
---
Identifier: de.haeckerfelix.Shortwave [desktop-application]
Name: Shortwave
Summary: Listen to internet radio
Bundle: flatpak:app/de.haeckerfelix.Shortwave/x86_64/stable
Homepage: https://gitlab.gnome.org/World/Shortwave
Icon: de.haeckerfelix.Shortwave.png
---
Identifier: com.getpostman.Postman [desktop-application]
Name: Postman
Summary: Platform for building and using APIs
Bundle: flatpak:app/com.getpostman.Postman/x86_64/stable
Homepage: https://www.postman.com
Icon: com.getpostman.Postman.png
---
Identifier: org.openshot.OpenShot [desktop-application]
Name: OpenShot Video Editor
Summary: An easy to use, quick to learn, and surprisingly powerful video editor
Package: openshot-qt
Bundle: flatpak:app/org.openshot.OpenShot/x86_64/stable
Homepage: https://www.openshot.org/
Icon: org.openshot.OpenShot.png
---
Identifier: com.boxy_svg.BoxySVG [desktop-application]
Name: Boxy SVG
Summary: Scalable Vector Graphics editor
Bundle: flatpak:app/com.boxy_svg.BoxySVG/x86_64/stable
Homepage: https://boxy-svg.com
Icon: com.boxy_svg.BoxySVG.png
---
Identifier: io.github.peazip.PeaZip [desktop-application]
Name: PeaZip
Summary: Free file archiver utility, open, extract RAR TAR ZIP archives
Bundle: flatpak:app/io.github.peazip.PeaZip/x86_64/stable
Homepage: https://peazip.github.io/
Icon: io.github.peazip.PeaZip.png
---
Identifier: engineer.atlas.Nyxt [desktop-application]
Name: Nyxt
Summary: The hacker's browser
Bundle: flatpak:app/engineer.atlas.Nyxt/x86_64/stable
Homepage: https://nyxt-browser.com/
Icon: engineer.atlas.Nyxt.png
---
Identifier: firefox.desktop [desktop-application]
Name: Firefox 網路瀏覽器
Summary: 瀏覽網際網路
Icon: firefox
---
Identifier: org.gnome.FileRoller [desktop-application]
Name: File Roller
Summary: Open, modify and create compressed archive files
Bundle: flatpak:app/org.gnome.FileRoller/x86_64/stable
Homepage: https://wiki.gnome.org/Apps/FileRoller
Icon: org.gnome.FileRoller.png
---
Identifier: org.gnome.FileRoller [desktop-application]
Name: File Roller
Summary: Open, modify and create compressed archive files
Package: file-roller
Homepage: https://wiki.gnome.org/Apps/FileRoller
Icon: file-roller_org.gnome.ArchiveManager.png



3 of 3: and brings out the following (had to run it as sudo, otherwise nothing happened. Discover then showed the known window "couldn't open appstream........."

QStandardPaths: XDG_RUNTIME_DIR not set, defaulting to '/tmp/runtime-root'
QStandardPaths: XDG_RUNTIME_DIR not set, defaulting to '/tmp/runtime-root'
QStandardPaths: XDG_RUNTIME_DIR not set, defaulting to '/tmp/runtime-root'
fetch ratings! true
adding empty sources model QStandardItemModel(0x55a26bbf8120)
QStandardPaths: XDG_RUNTIME_DIR not set, defaulting to '/tmp/runtime-root'
packagekitqt.transaction: Unknown Transaction property: "Sender" QVariant(QString, ":1.174")
QStandardPaths: XDG_RUNTIME_DIR not set, defaulting to '/tmp/runtime-root'
QStandardPaths: XDG_RUNTIME_DIR not set, defaulting to '/tmp/runtime-root'
QStandardPaths: XDG_RUNTIME_DIR not set, defaulting to '/tmp/runtime-root'
took really long to fetch FlatpakBackend(0x55a26bb28530)
took really long to fetch PackageKitBackend(0x55a26bbea040)
packagekitqt.transaction: Unknown Transaction property: "Sender" QVariant(QString, ":1.174")
packagekitqt.transaction: Unknown Transaction property: "Sender" QVariant(QString, ":1.174")
no component found for "org.kde.neon.neon"
qml: Error: Could not open appstream://google-chrome.desktop because it was not found in any available software repositories.
Please report this issue to the packagers of your distribution.
Please visit https://bugs.kde.org/
QStandardPaths: XDG_RUNTIME_DIR not set, defaulting to '/tmp/runtime-root'
QStandardPaths: XDG_RUNTIME_DIR not set, defaulting to '/tmp/runtime-root'
QStandardPaths: XDG_RUNTIME_DIR not set, defaulting to '/tmp/runtime-root'

Add on to my answer:
Under number 3  `plasma-discover appstream://google-chrome.desktop` is missing.

The produced text belongs to this command.

cms

> had to run it as sudo
Hmm, that's not something I'd expect you have to do.

Is this the first time you ran Discover or any other app with `sudo`, or have you done it before? If so, which apps?

Can't say if it's the first time or if I ever done it before. Just came to my mind to try it this way. Tried it again without and it again didn't work.
And I get the notice: Running as root is discouraged and unnecessary.

In general running an app with `sudo` isn't a valid troubleshooting technique nor method of solving problems, and in fact it usually causes new problems that are then hard to debug.

Anyway, I do see an AppStream component matching "google-chrome.desktop" so it's not clear to me why `plasma-discover appstream://google-chrome.desktop` isn't working. That's probably our bug.